Some ideas about programming tools and techniques, microcomputers and free and open software than can be used when working with Art and Microcomputers

Saturday, February 6, 2016

The Cypress PSoC 5LP

I recently started to work on a project that needs several analog input and output channels connected to some sensors and a PID control loop and it will probably work better with 5V than the currently popular 3.3 for Cortex M systems. So I decided to dig out a CY8CKIT-059 PSoC 5LP Prototyping Kit that has been gathering dust waiting for the right project to come along.

This is actually an amazing chip, even if the processor is a standard Cortex-M3 that runs up to 80MHz (there are signs that Cypress is working on a PSoC7 with a M7 core and probably a price to match). The
64K RAM and 256K FLASH sizes are modest but what makes this chip special are
the configurable analog and digital blocks on the chip. There are three ADC's, one with high impedance buffers, two
DAC's and four opamps, all connected to an analog switching network. The digital side has a number of universal digital blocks to implement
your own digital logic or preconfigured communication interfaces and a digital filter block, DFB. This is a 24 bit datastream co-processor with a multiply-accumulate unit and a ALU. The analog and digital I/O can be run from 1.71 to 5.5 volts.

The vendor supplied tool chain PSoC Creator
only runs under Windows but it is not a bad experience even though I am
always skeptic of systems that generates code that is hard to know
where one can change and how. I find it often less trouble to implement
stuff directly from the data sheet than to learn the ins and outs of the
library calls. In order to use the extra analog and digital blocks in
the chip I think it is really necessary to use the vendor supplied
toolchain, and without these extras the chip is not very special.

Add
the fact that the CY8CKIT-059 PSoC 5LP Prototyping Kit can be bought
for $10 this is definitely a system worth trying out, even if USB
connectors made from four strips on top of the circuit board is not the
most professional and stable connection method. That can be fixed with
an old USB cable and a soldering iron, and the price will still be
attractive. The on board programmer and debugger is also a programmable PSoC 5LP and could be used for a project requiring very few I/O pins.

Getting started is quite easy, install some USB drivers, the PSoC Creator and PSoC Programmer software with example projects. Open an example project and hit the debug button. I started with the "CE95277 ADC and UART" project and soon had the board sending ADC samples over USB serial to my PC. Getting used to all the tools and panels takes a few days but the help functions are easy to access and components have datasheets and code examples the opens with a right click.

About Me

Mathematician working at the engineering faculty at University of Borås. Got a BFA as a teacher of Classical Ballet a long time ago and have worked on the use of technology in art. Have produced software and hardware for the Opera Mechatronica.